Millisecond Anneal and Short-Channel Effect Control in Si CMOS Transistor Performance

In this letter, the effects of the millisecond anneal in conjunction with conventional spike anneal on the p-n junction formation in CMOS devices are studied. The results reveal that the millisecond and spike annealing sequence plays an important role in the implanted boron p+/n junction formation. On blanket Si wafers, the millisecond anneal followed by the spike anneal increases implanted boron solid solubility in crystalline silicon by ~18% compared to that obtained using reversed annealing sequence under the same annealing conditions. This result substantially alters the short-channel effect behaviors in the fabricated CMOS devices, resulting in opposite threshold-voltage behaviors in PMOS and NMOS devices when using boron as NMOS halo implant. The results also provide useful insights into ultrashallow-junction formation and short-channel effect control when scaling CMOS technology